Dual switched live splitting

Hey all, need a spot of help if anyone can help.

Customer has an inline fan that draws from a bthroom and adjacent toilet, both have switched L feeds to the isol s/w. What is the best way of preventing backfeed to the lighting in the other room? My thought would have been a relay but any other ideas would be most appreciated!

Double pole switches for the lights in the two rooms.  It will have to be a 20A DP switch (as they don't make them smaller) so may not be identical to the other light switches in the house but not far off if you choose the right make.

Fantastic, thanks for that Dave. Didn't even cross my mind to use dp switches

very common in some older houses. always fun to fault find after some clueless idiot has replaced a light switch with a normal one not knowing why a DP was fitted to start with

Andy™ said:

very common in some older houses. always fun to fault find after some clueless idiot has replaced a light switch with a normal one not knowing why a DP was fitted to start with

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Ahem!

i was that clueless idiot when I was an apprentice!

i got shouted at

ProDave said:

Double pole switches for the lights in the two rooms.  It will have to be a 20A DP switch (as they don't make them smaller) so may not be identical to the other light switches in the house but not far off if you choose the right make.

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Scolmore do 10A DP minigrid switches

I often use them for outside lights to isolate possible RCD trip issues if there is a fault

UNG said:

I often use them for outside lights to isolate possible RCD trip issues when there is a fault

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edited that for you!

Anything outside -  I always fit DP isolation 

Kernowspark said:

 What is the best way of preventing backfeed to the lighting in the other room? 

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so what is the issue? has someone changed something??